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schema builder laravel migrations unique on two columns
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288
The second param is to manually set the name of the unique index. Use an array as the first pa...
jQuery slide left and show
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edited Aug 22 '12 at 9:43
Urbycoz
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Select Row number in postgres
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answered Aug 14 '12 at 12:29
vyegorovvyegorov
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Cannot pass null argument when using type hinting
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362
PHP 7.1 or newer (released 2nd December 2016)
You can explicitly declare a variable to be null ...
R object identification
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128
I usually start out with some combination of:
typeof(obj)
class(obj)
sapply(obj, class)
sapply...
How to override the [] operator in Python?
...thod.
class MyClass:
def __getitem__(self, key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too, otherwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last)...
POST JSON to API using Rails and HTTParty
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2 Answers
2
Active
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Why do we have map, fmap and liftM?
...r see an error about lists than about Functors.
-- Typeclassopedia, page 20
fmap and liftM exist because monads were not automatically functors in Haskell:
The fact that we have both fmap and liftM is an
unfortunate consequence of the fact that the Monad type class does not require
a Func...
Does a valid XML file require an XML declaration?
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In XML 1.0, the XML Declaration is optional. See section 2.8 of the XML 1.0 Recommendation, where it says it "should" be used -- which means it is recommended, but not mandatory. In XML 1.1, however, the declaration is mandatory. See section 2.8 of the XML 1.1 Recommendation, where...